Abstract: The outrunner motor includes a rotor housing designed as a rotor bell with rotor poles situated in the rotor bell. The rotor bell is mountable in a stator of the outrunner motor so as to be rotatable about an axis of rotation and exhibits a rigidity that is asymmetrical in relation to the axis of rotation, in particular an asymmetrical tilting rigidity. The outrunner motor also has a motor shaft, a stator with a plurality of stator teeth, and a rotor surrounding the stator. The rotor allows the outrunner motor to be quieter and have lower levels of vibration. The center of gravity of the rotor bell is located on an axis of rotation.

Abstract: In a device for reducing resonant vibrations of rotor blades in turbomachines, cavities for the selective disturbance of the flow are arranged between the rotating blade tip and that wall of the casing which bounds the flow duct. These cavities are arranged in the casing wall in the region of the blade tips and comprise a plurality of cavities arranged over the circumference. Their open cross section facing the flow duct is arranged in the axial planes bounded by the inlet edges and outlet edges of the rotor blades.